Tesla Motors officially unveiled an update to the Tesla Roadster, the two-seater sports car that was also the company’s first car. It’s Tesla’s “Roadster 3.0 package.”
CEO Elon Musk hinted at the upcoming update in a tweet to a fan earlier this week, and again on Christmas Day.
Roadster upgrade will enable non-stop travel from LA to SF — almost 400 mile range. Details tmrw. Merry Christmas!
— Elon Musk (@elonmusk) December 25, 2014
In the Friday blog post, the Tesla Motors team describes how the Roadster’s new “3.0 package” applies what the company learned in terms of batteries, rolling resistance, and aerodynamics.
For example, the original Roadster was powered by a lithium-ion battery — it was the first time that had been put into production for any vehicle. But thanks to new cell technology, Tesla’s new battery pack for the Roadster delivers about 70kWh in the same size pack — 31% more energy than the original Roadster cell.
Mind you, the original Roadster had about a 245-mile range. With this new battery and “a set of speeds and driving conditions,” Tesla says it “can confidently drive the Roadster 3.0 over 400 miles.”
Tesla says it will be demonstrating its new-and-improved range “during a non-stop drive from San Francisco to Los Angeles in the early weeks of 2015.” As a Tesla spokeswoman pointed out to us, “the drive from LA to SF is, in fact, 381 miles.”
To get such an improvement in range, Tesla also had to make the Roadster more aerodynamic. The company says it’s reduced the drag coefficient to make a 15% improvement, according to the company’s own maths.
Tesla says it’s also rolling out new tires that are 20% improved. With all of these improvements, Tesla says the new Roadster can achieve a “40-50% improvement on range” over the original Roadster.
Unfortunately, Tesla has no new battery enhancements to announce for the Model S.
Should mention that a battery pack upgrade is not coming soon for the Model S, but it obviously *will* happen long-term.
— Elon Musk (@elonmusk) December 26, 2014
Here’s the full blog post:
The Roadster 3.0 package applies what we’ve learned in Model S to Roadster. No new Model S battery pack or major range upgrade is expected in the near term.
Battery technology has continued a steady improvement in recent years, as has our experience in optimising total vehicle efficiency through Model S development. We have long been excited to apply our learning back to our first vehicle, and are thrilled to do just that with the prototype Roadster 3.0 package. It consists of three main improvement areas.
The original Roadster battery was the very first lithium ion battery put into production in any vehicle. It was state of the art in 2008, but cell technology has improved substantially since then. We have identified a new cell that has 31% more energy than the original Roadster cell. Using this new cell we have created a battery pack that delivers roughly 70kWh in the same package as the original battery.
The original Roadster had a drag coefficient (Cd) of 0.36. Using modern computational methods we expect to make a 15% improvement, dropping the total Cd down to 0.31 with a retrofit aero kit.
3. Rolling Resistance
The original Roadster tires have a rolling resistance coefficient (Crr) of 11.0 kg/ton. New tires that we will use on the Roadster 3.0 have a Crr of roughly 8.9 kg/ton, about a 20% improvement. We are also making improvements in the wheel bearings and residual brake drag that further reduce overall rolling resistance of the car.
Combining all of these improvements we can achieve a predicted 40-50% improvement on range between the original Roadster and Roadster 3.0. There is a set of speeds and driving conditions where we can confidently drive the Roadster 3.0 over 400 miles. We will be demonstrating this in the real world during a non-stop drive from San Francisco to Los Angeles in the early weeks of 2015.
We are confident that this will not be the last update the Roadster will receive in the many years to come.